Since 1 June 2026, Vietnam has run on E10, and the bike you rent in Hanoi is almost certainly burning it already. You do not need to do anything differently. The short version: ask the rental shop which grade the bike takes, keep using that grade, and stop reading. The longer version below covers the three situations where E10 genuinely matters — none of which apply to a bike in daily use.
What you can buy at a Vietnamese pump since June 2026
Table of contents13
Table of contents13
Under Circular 50/2025/TT-BCT, unleaded mineral petrol must be blended into E10 for petrol engines nationwide from 1 June 2026. The familiar RON 95 was replaced by E10 RON 95. The part most summaries skip: E5 RON 92 continues to be blended and supplied for petrol engines until the end of 2030, so there is still a choice at the pump rather than a single grade.
| Grade | Ethanol | Status since 1 June 2026 |
|---|---|---|
| E10 RON 95 | 10% | The common grade; replaced the old RON 95 |
| E5 RON 92 | 5% | Still supplied for petrol engines until end of 2030 |
| Mineral RON 95 (no ethanol) | 0% | Replaced by E10 RON 95 |
One honest caveat: we could not find an official source confirming the status of RON 97 after the switchover, so we are not going to claim it is either available or withdrawn. The price board at the pump is the reliable answer on the day.
What E10 is, and how it differs from E5
If you ride at home in the UK, Ireland, Australia or much of the US, you already know this part: the number after the E is the percentage of bioethanol blended into the fuel. E10 is roughly 10%, E5 roughly 5%, the rest is mineral petrol.
The part worth noting as a visitor is the octane rating attached to each grade in Vietnam. E10 here is RON 95; the lower-ethanol option is RON 92, not RON 95. So choosing between the two is not only an ethanol decision — you are changing octane at the same time. That is different from the UK, where E10 and E5 are both commonly sold at 95 and the E5 option is usually the higher-octane super grade.
Is E10 safe for motorbikes
The Vietnam Association of Motorcycle Manufacturers (VAMM) states that motorbikes from its member brands can switch to E10, including models 20 to 25 years old. That is a statement from the manufacturers’ association about its members’ bikes — not a blanket guarantee covering every petrol vehicle on Vietnamese roads.
On materials: ethanol does not harm the metal components of an engine. The concern is the non-metal parts — gaskets, seals and some older rubber fuel lines can be affected by prolonged contact with a higher ethanol content than they were designed around.
Older bikes and carburettor engines
Ethanol draws moisture from the air. Fuel-injected engines are less exposed because the fuel system is sealed. Carburettor engines are more sensitive to it, particularly when a bike sits unused for days in high humidity — which describes northern Vietnam for a good part of the year.
The practical consequence is reassuring: a bike in regular use rarely sees the problem at all, because the fuel in the tank is replaced continuously and never sits long enough to absorb much moisture. A rental bike is, almost by definition, a bike in regular use.
Three real issues: bikes left standing, tank deposits, rubber seals
These are the situations VAMM and Vietnamese engine specialists flagged around the switchover.
1. A bike left standing may become hard to start. Bioethanol attracts water, so fuel sitting in a tank for weeks degrades faster than it used to. The fix is to start the engine and ride it briefly from time to time rather than leaving it untouched.
2. Old metal tanks can shed deposits. Ethanol cleans the fuel system. On a bike with years of accumulated residue in a metal tank, that layer can loosen, travel with the fuel and clog the filter or injector. The damage was not caused by E10 — it is old sediment being dislodged — but the outcome is still a bike that cuts out on the road if it is not dealt with.
3. Gaskets and non-metal parts. On a very old machine whose fuel-system seals have never been replaced, this is the group a mechanic should look at during routine servicing.
VAMM’s advice across all three is the same: have the fuel system inspected periodically. None of it is an argument against using E10 — it is an argument for normal maintenance on old machines.
How much fuel economy and power change
Ethanol carries less energy per litre than mineral petrol, so the same litre does slightly less work. The figures reported around the switchover:
- Power: varies by roughly ±5%, depending on the engine and how it is tuned.
- Consumption: may rise by around 1–3%.
On a scooter in Hanoi traffic, 1–3% is a few thousand dong per tank. It is small enough to ignore when planning a trip, and large enough that you should not be puzzled if the gauge drops marginally faster than you expected.
What to put in a rental bike
As a renter you are in a different position from an owner: you do not know the bike’s age, its service history, or what it has been running on. So keep it simple.
- Ask at pickup which grade the bike currently runs on and which to keep using. It takes ten seconds and settles everything else in this article.
- Stick with that grade for the whole rental rather than alternating between E10 RON 95 and E5 RON 92 tank by tank.
- Do not pick by habit from home. The grade names and octane ratings here do not line up with the ones you are used to.
- At the pump, say the grade out loud or point at the price board — attendants fill the tank for you, and it is normal to specify.
At Mr Tú – Old Quarter Motorbike Rental, just ask when you collect the bike: staff will tell you which grade that specific bike runs on and which one to keep putting in.
FAQ
I accidentally filled with the wrong grade. Is that a problem?
According to VAMM, member-brand motorbikes can run on E10. A single tank of the other legally sold petrol grade is not an emergency. If the bike behaves oddly afterwards, have the fuel system checked. Both are legally sold petrol grades for petrol engines. Still, staying on one grade is the simplest way to know how the bike is behaving — particularly on a bike that is not yours. Fuel prices here are revised on a regular cycle, so this article does not quote one. The posted board at the pump is accurate on the day you fill up. No. The E10 requirement covers fuel for petrol engines only. Ask the shop — they know the model year and the service history. For a bike in daily use and serviced regularly, this is not something to plan around. A week is not long. If it will stand for several weeks, starting it and riding briefly is worth doing — though on a rental that long, the shop will usually advise you themselves.Can E10 and E5 be mixed in the same tank?
Is E10 cheaper or more expensive?
Does any of this apply to electric bikes?
My rental bike looks old. Should I be worried?
Do I need to do anything if the bike sits parked for a week mid-trip?
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